A client-server system which performs data transmission/reception between a server and a client through a communication line is conventionally known (for example, see Patent Literature 1 below). In such a client-server system, when a communication line is disconnected during data communication and is thereafter restored, data temporarily held by the server is retrieved after the line restoration and is retransmitted to the client. This allows communication between applications to be automatically resumed after the recovery from disconnection.
On the other hand, in recent years, mobile communication terminals such as mobile phones have been equipped with the short-range communication function such as infrared communication, Bluetooth communication, and non-contact IC card communication. In such mobile communication terminals, data downloaded from a mobile communication network is transferred to, for example, a personal computer through short-range communication.